DE 44 23 422 A1 discloses a method for externally superfinishing a rotationally symmetrical body, in which method the body is moved in a rotating manner, a finishing tool is moved in an oscillating manner in a direction parallel to the rotational axis and in which a further movement in a direction parallel to the rotational axis is superimposed on the oscillating movement of the finishing tool.
This method is also known under the heading of “finish-machining with superposition stroke” and has the advantage that a profile of a finish-machined workpiece surface is adjustable in a varying manner by a cylindrical shell surface. A slightly convex crankshaft bearing surface, for example, can be produced in this way.
However, the method known from DE 44 23 422 A1 suffers from the disadvantage that in order to set up the finishing device for a crankshaft or camshaft of a particular shape, it requires a relatively high degree of setup complexity. The dimensions, which are relevant to the finish-machining, of workpieces of this type are in particular the diameter and seat width of the main bearings and additional bearings to be machined, the axially parallel distance of the bearings relative to one another and the offset of the additional bearing relative to the workpiece axis.
In motor construction, there is a trend to standardise the dimensions relevant to different motors having different numbers of cylinders and, for example, to select the inside micrometer of the motors (the distance between the cylinder axes) to be identical irrespective of the number of cylinders and also as far as possible to use identical main bearing diameters and seat widths.